Did European libraries really chain books to prevent theft?

Yes. Some European libraries used chains to secure books during the Middle Ages and the early modern period. Readers could consult the volumes without being able to carry them away.

Hereford Cathedral describes a surviving system in which chains connect book covers to rods along the shelves. Book historian Erik Kwakkel also identifies surviving chains and attachment marks on historical bindings as evidence of this security practice.

The chains protected access to valuable objects rather than making reading impossible. At Hereford, books face outward with their page edges visible so they can be opened without tangling the chains. Its surviving library arrangement dates from the seventeenth century, although the practice is older.